PSLE Roshel had a bag of red balls and gold balls in the ratio 16 : 9. She removed an equal number of red balls and gold balls from the bag. The ratio of the number of red balls and gold balls left in the bag became 8 : 1. What percentage of the balls were left in the bag?
|
Red balls |
Gold balls |
Difference |
Total |
Before |
16x1 = 16 u |
9x1 = 9 u |
7x1 = 7 u |
25x1 = 25 u |
Change |
- 8 u |
- 8 u |
|
|
After |
8x1 = 8 u |
1x1 = 1 u |
7x1 = 7 u |
9x1 = 9 u |
When Roshel removed an equal number of red balls and gold balls, the difference between the number of red balls and gold balls at first and in the end remains the same.
LCM of 7 and 7 is 7.
Percentage of the balls left in the bag
=
925 x 100%
= 925 x 100%
= 36%
Answer: 36%